Centrin-deficient Leishmania mexicana confers protection against New World cutaneous leishmaniasis

Greta Volpedo; Thalia Pacheco-Fernandez; Erin A Holcomb; Wen-Wei Zhang; Patrick Lypaczewski; Blake Cox; Rebecca Fultz; Chelsea Mishan; Chaitenya Verma; Ryan H Huston; Abigail R Wharton; Ranadhir Dey; Subir Karmakar; Steve Oghumu; Shinjiro Hamano; Sreenivas Gannavaram; Hira L Nakhasi; Greg Matlashewski; Abhay R Satoskar

doi:10.1038/s41541-022-00449-1

Centrin-deficient Leishmania mexicana confers protection against New World cutaneous leishmaniasis

NPJ Vaccines. 2022 Mar 2;7(1):32. doi: 10.1038/s41541-022-00449-1.

Authors

Greta Volpedo^{1

2}, Thalia Pacheco-Fernandez², Erin A Holcomb², Wen-Wei Zhang³, Patrick Lypaczewski³, Blake Cox², Rebecca Fultz², Chelsea Mishan², Chaitenya Verma², Ryan H Huston², Abigail R Wharton², Ranadhir Dey⁴, Subir Karmakar⁴, Steve Oghumu², Shinjiro Hamano⁵, Sreenivas Gannavaram⁴, Hira L Nakhasi⁶, Greg Matlashewski⁷, Abhay R Satoskar^{8

9}

Affiliations

¹ Department of Microbiology, The Ohio State University, Columbus, OH, 43210, USA.
² Department of Pathology, Wexner Medical Center, The Ohio State University, Columbus, OH, 43210, USA.
³ Department of Microbiology and Immunology, McGill University, Montreal, QC, Canada.
⁴ Division of Emerging and Transfusion Transmitted Diseases, CBER, FDA, Silver Spring, MD, USA.
⁵ Department of Parasitology, Institute of Tropical Medicine (NEKKEN), The Joint Usage/Research Center on Tropical Disease, Nagasaki University, Nagasaki University Graduate School of Biomedical Sciences Doctoral Leadership Program, Nagasaki, Japan.
⁶ Division of Emerging and Transfusion Transmitted Diseases, CBER, FDA, Silver Spring, MD, USA. [email protected].
⁷ Department of Microbiology and Immunology, McGill University, Montreal, QC, Canada. [email protected].
⁸ Department of Microbiology, The Ohio State University, Columbus, OH, 43210, USA. [email protected].
⁹ Department of Pathology, Wexner Medical Center, The Ohio State University, Columbus, OH, 43210, USA. [email protected].

Abstract

Leishmaniasis is a neglected protozoan disease affecting over 12 million people globally with no approved vaccines for human use. New World cutaneous leishmaniasis (CL) caused by L. mexicana is characterized by the development of chronic non-healing skin lesions. Using the CRISPR/Cas9 technique, we have generated live attenuated centrin knockout L. mexicana (LmexCen^-/-) parasites. Centrin is a cytoskeletal protein important for cellular division in eukaryotes and, in Leishmania, is required only for intracellular amastigote replication. We have investigated the safety and immunogenicity characteristics of LmexCen^-/- parasites by evaluating their survival and the cytokine production in bone-marrow-derived macrophages (BMDMs) and dendritic cells (BMDCs) in vitro. Our data shows that LmexCen^-/- amastigotes present a growth defect, which results in significantly lower parasitic burdens and increased protective cytokine production in infected BMDMs and BMDCs, compared to the wild type (WT) parasites. We have also determined the safety and efficacy of LmexCen^-/- in vivo using experimental murine models of L. mexicana. We demonstrate that LmexCen^-/- parasites are safe and do not cause lesions in susceptible mouse models. Immunization with LmexCen^-/- is also efficacious against challenge with WT L. mexicana parasites in genetically different BALB/c and C57BL/6 mouse models. Vaccinated mice did not develop cutaneous lesions, displayed protective immunity, and showed significantly lower parasitic burdens at the infection site and draining lymph nodes compared to the control group. Overall, we demonstrate that LmexCen^-/- parasites are safe and efficacious against New World cutaneous leishmaniasis in pre-clinical models.

Grants and funding

R21 AI138555/AI/NIAID NIH HHS/United States